Small Diameter Gages

Pitch diameter and functional size inspections are pivotal to nearly every threaded connection. This can be especially true in smaller diameters, but these smaller diameters require a unique gage design to perform the proper inspections.

The SPG-6000 line of thread inspection gages measures internal and external functional size and pitch diameter of thread diameters between .625″ and 1.500″. Mainly, these gages are used on ANSI and ISO standard straight thread forms. Primarily among these groups, the gages are used on the ACME, Stub Acme, Stub ACME Modified-1 & -2, Metric & MJ, and UN, UNJ, & UNR Series of threads. However, these gages are versatile in that they can be modified to inspect nearly any type of thread in our .625″ to 1.500″ size range. The SPG-6000 can be equipped with either thread rolls or contact points. Contact points are applied for pitch diameter measurement, while thread rolls inspect functional size.

Pitch diameter inspection requires the addition of contact point arms to hold the contact points. Contact point arms are sold in sets of two. Our standard contact point arms require straight shank contact points. Contact point arms designed for threaded shank contact points are available at additional cost.

For functional size inspection, thread rolls attach directly to the gage. Thread rolls for certain thread types may have a designated set for internal threads or external threads, while other thread types have one set of rolls for both internal and external.

Thread Rolls for Small Internal Diameter Functional Size Inspection

Gagemaker offers matched precision ground thread rolls for a variety of small diameter thread types. Thread rolls attach directly to the gage. If you do not find your pitch or thread type listed, additional thread rolls may be available. Please contact customer service for more.

Small diameter metric thread rolls are available as separate internal or external sets. SRMI thread rolls inspect the internal functional size of machine threaded parts with metric and MJ 60° “V” thread forms, while “TRME” rolls are used for externally threaded parts. Please ensure you select the corresponding internal or external application when ordering.

Rolls are sold in matched sets (2 rolls). Rolls sold separately from gages and software. Please specify the pitch of thread when ordering. If you do not find your pitch listed, thread rolls may be still available. Please contact customer service for more.

Small diameter UN, UNJ, & UNR series thread rolls are used to inspect the internal functional size of machine threaded parts with UN, UNJ, & UNR 60° “V” thread forms. Rolls are specifically designed for use on parts threaded externally (“SRVE”) or internally (“SRVI”). Please ensure you select the corresponding internal or external application when ordering.

Rolls are sold in matched sets (2 rolls). Rolls sold separately from gages and software. Please specify the pitch of thread when ordering. If you do not find your pitch listed, thread rolls may be available. Please contact customer service for more.

To measure pitch diameter on small diameters with our SPG-6000 series of gages, contact points and contact point arms are required.

Gagemaker’s contact points are manufactured with carbide balls. Standard contact diameters are held to tolerances of ± .0002″. Contact point sizes are matched closely to thread inspection wire sizes. These contact point sizes are used in the TDWIN™ software program (sold separately). Contact points are sold individually and separately.

“SP” contact points only fit straight shank “SPA” contact point arms. Our “STPA” threaded shank contact point arms require threaded shank contact points, found here. Contact point arms are sold separately as a set of two.

Below, we’ve provided a list of our more popular straight shank contact points and contact point arms. However, if you do not find your pitch or thread type listed or need custom contact points, please contact customer service for more.

If you do not find your pitch listed, please contact customer service for more information.

Pitch

Description

Model

5

5 pitch straight shank contact point

SP-105

6

6 pitch straight shank contact point

SP-096

7

7 pitch straight shank contact point

SP-096

8

8 pitch straight shank contact point

SP-072

9

9 pitch straight shank contact point

SP-072

10

10 pitch straight shank contact point

SP-057

11

11 pitch straight shank contact point

SP-050

11.5

11.5 pitch straight shank contact point

SP-050

12

12 pitch straight shank contact point

SP-050

13

13 pitch straight shank contact point

SP-041

16

16 pitch straight shank contact point

SP-041

18

18 pitch straight shank contact point

SP-032

20

20 pitch straight shank contact point

SP-032

24

24 pitch straight shank contact point

SP-032

28

28 pitch straight shank contact point

SP-021

32

32 pitch straight shank contact point

SP-021

About Us

Gagemaker develops and manufactures precision mechanical inspection equipment for the Oilfield, Mining, Water Well, and General Machining industries. Gagemaker products are used in countless facilities around the world. Gagemaker's commitment to actively developing new products along with their superb customer service has set the industry standard for 30 years.